You could do 
fill_hashref (my $href = []);

[download]
Aliasing is the trick, observe 
use DDS;
my @snot = 1 .. 2;
Dump(\@snot);
blot(@snot);
Dump(\@snot);
glot(@snot);
Dump(\@snot);
sub blot {
  $_++ for @_; # @_ holds aliases, $_ also aliases
  return;
}
sub glot {
   my( @copies ) = @_;
   $_++ for @copies;
   return;
}
__END__
$ARRAY1 = [
            1,
            2
          ];
$ARRAY1 = [
            2,
            3
          ];
$ARRAY1 = [
            2,
            3
          ];

[download]
See Data::Alias for 
alias my ($x, $y) = @_;     # named aliases to arguments

[download]

In reply to Re: Populating an undefined hashref in a sub by Anonymous Monk
in thread Populating an undefined hashref in a sub by NetWallah

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